Functional heterogeneity of large and small resistance arteries isolated from biopsies of subcutaneous fat - Implications for investigation of vascular pathophysiology

Few studies using human subcutaneous resistance arteries acknowledge the possibility of functional heterogeneity in these vessels. Large (similar to 500 mum) and small (greater than or equal to 200 mum) resistance arteries (n = 11) and veins (it = 5) were identified using physical, structural and functional criteria in 14 biopsies of human gluteal fat. Endothelium-dependent relaxation was not evident in veins, while, unlike small resistance arteries (E-max 95.74 +/- 1.86%; -log IC50 7.28 +/- 0.09), large resistance arteries with an intact endothelium failed to respond to acetylcholine. These results suggest that large resistance arteries may lack muscarinic receptors on the,endothelium and emphasise the importance of careful vessel selection and characterisation in studies using human resistance arteries. (C) 2001 Elsevier Science Inc. All rights reserved.